U.C. Davis is working with an international network of teams sometimes known as “virus hunters.” They travel the world, connecting the dots between viruses that move from animals to people.
One of the leaders of the effort is Christine Johnson, a top disease detective, whose research indicates the health of wild animals and the protection of their habitats is a critical key to preventing global disease outbreaks in the future.
“It’s no surprise that COVID-19 came from a wild animal. We suspect, based on the genetic evidence, that it came from a bat species,” Johnson said. It is still not certain if the virus may have first spread from a bat to another species, which then infected humans.
Scientists believe most infectious diseases that affect people came from animals over many centuries. They are known as zoonotic diseases. Many emerged as people domesticated animals, including illnesses most people “don’t even recognize as having come from animals, like HIV, even measles and mumps are suspected genetically or evolutionarily to have come from animals” according to Johnson.
Even so, domestic animals are not the biggest concern right now. Johnson believes the more worrisome trend is infectious diseases, including the Ebola virus, that have emerged over the last 20 to 30 years and have come almost entirely from wildlife.
But Johnson said we should not blame the wild animals who she calls “victims” as well. Her team’s newly released research looked at 142 viruses believed to have jumped from animals to people – and the data points to human activities as the driving force.
“Those same activities that cause species to go extinct are the same activities that are causing increased public health risk,” Johnson said.
According to Johnson biodiversity helps regulate disease, but as people drastically change the natural environment we end up with too many or too few of certain species – and that increases the risk of another pandemic.
Habitat destruction is a critical part of the puzzle. Some wild species adapt when their habitat disappears. They move into human communities, living near homes and bringing their mutating diseases with them to infect people.
Other wild animals are forced into human contact. “These are species that have been hunted or over-hunted” Johnson said. “Species that are trafficked in the wildlife trade are typically brought out of the wild alive. They are put into cages with others in very dense sort of crowded conditions that fosters disease transmission.” The animals’ health is compromised by stress and they come in contact with other species they would never meet in the wild, adding to the likelihood they will share their viruses, Johnson said.
There is widespread scientific agreement COVID-19 emerged from a wild animal in those kind of conditions, according to Johnson. That is leading to a growing call to shutdown down wildlife markets, but Johnson’s research indicates we need to pay attention to the entire environment as well.
“If we start to recognize that and think more carefully about habitat change and how that is affecting wildlife, we can start to reduce disease spillover of viruses from animals into humans and minimize pandemics in the future” she said.
If you have a question or comment about the coronavirus pandemic, submit yours via the form below or here.
Get the latest news, information and videos about the novel coronavirus pandemic hereRELATED STORIES & VIDEOS:
Copyright © 2020 KGO-TV. All Rights Reserved.